SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54514fffbcacf61ace831e479844764ede824af00b395cacf40b2347890b2c52' 
  AND token = 'H2zRbsOVO/tf2CgAFcLiin2+xwg2tB/DDpNuoWORE8M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}